Primary contact

ORCID ID

Contact details

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

Project 2005.2; NTR314

Study information

Scientific title

Acronym

Study hypothesis

1. Oral anticoagulant control is less stable at a low average intake of vitamin K2. As a consequence, a low dose vitamin K supplement results in a more stable anticoagulant effect in patients using vitamin K antagonists (VKA)3. Dietary intake of vitamin K is associated with sensitivity to VKA and stability of anticoagulant treatment4. Polymorphisms of the VKORC1 gene are associated with sensitivity to VKA and stability of anticoagulant treatment

Intervention

Intervention type

Phase

Drug names

Primary outcome measure

1. Quality of anticoagulant treatment2. Expressed as time in therapeutic range

Secondary outcome measures

1. Number of international normalised ratios (INRs) in therapeutic range2. Bleeding and thromboembolic complications

Overall trial start date

16/11/2004

Overall trial end date

01/06/2006

Reason abandoned (if study stopped)

Eligibility

Participant inclusion criteria

1. Patients treated at the Leiden anticoagulation clinic with an indication for long-term oral anticoagulant therapy using the vitamin K antagonist phenprocoumon2. Age between 18 and 80 years3. Informed consent

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

200

Participant exclusion criteria

1. Treatment by a medical specialist for liver failure2. Haemo or peritoneal dialysis3. Pregnancy or a planned pregnancy, puerperium4. Any chronic condition with an expected median survival of less than 6 monthsan expected interruption of oral anticoagulant treatment of more than 1 week5. Self-management of oral anticoagulant therapy6. Other drugs affecting haemostasis (aspirin, heparin, clopidogrel)